Field of the Invention and Description of the Prior Art
This invention relates to an improved mechanism for opening and closing the molds provided on a glass forming machine.
Glass products are formed in a variety of ways, one being by the provision of upwardly facing molds. A glass gob is delivered into the cavity of each mold and subsequently a press ram is driven down into the cavity to cooperate with the mold cavity to form the molten glass gob to the desired shape. Thereafter, the article must be formed and cooled at subsequent stations, the mold must be opened, and the glass product must be removed.
In conventional glass molding machines, the molds are rotated through 360.degree. for one cycle of operation, from delivery of the glass gob through forming, cooling, take out, and mold preparation for receiving another glass gob. Generally, the mold includes a linkage which may be operated by a cylinder to open the mold at the take out position for removal of the glass product and a cam for subsequent closing of the mold at the delivery station. Generally, the cam is a 360.degree. cam that holds the mold closed from the delivery station through the take out station with the cylinder opening the mold at the take out station and the cam closing the mold before it is rotated to the glass delivery station. Most of the conventional glass making machines operate with a 360.degree. cycle.
In certain application, however, the molds may be rotated through more than 360.degree., such as two full revolutions or 720.degree.. In such a system, the use of the 360.degree. mold is unsatisfactory because the opening and closing of each mold takes place in a second 360.degree. of mold revolution.